A Matter for Negotiation
by TungstenCat
Summary: Sakura doesn't care about what the world will say. The world already abandoned her countless times, and tried to keep her from the two people she loves most. Now that she has been freed from her shackles, she doesn't want to waste any more time hesitating. Slightly AU Post-UBW, mostly rated M for pairing rather than content.


**Author's Note**: I know people read my stuff for the femslash, and while this story does have some of that, it's outside the kind of thing I usually write. This is what happens when you discuss inappropriate pairings on a Discord server, and your stupid mouth ends up writing cheques you have to cash later. Basically the prompt ended up boiling down to "Rin x Sakura fluff, with lots of Shirou and just a twist of citrus." And while this tagging often refers to Rin and Sakura as effective sister-wives, both in sexual relationships with Shirou but not with each other, that is... not the case here. You have been warned.

* * *

"Now just the raspberries for the finishing touch." Shirou deftly places the red fruit on top of the snowy expanse of whipped cream that crowns the elaborate trifle.

"That looks wonderful, senpai! I'm sure Neesan will love it."

Sakura rests her elbows on the table as she leans over to admire his handiwork. She considers herself rather talented when it comes to Western desserts, but even she has to admit defeat in the face of the young man's talent and enthusiasm. He has taken to traditional English cooking like a duck to water. Still, she can't find it in herself to be too upset so long as she and her sister are the beneficiaries.

"I hope it cheers her up a bit," he says as he wipes his hands clean on a cloth. "She didn't look very happy about the reception."

Sakura giggles. "That's just because Edelfelt-san is also there. But I'm sure coming home to something this tasty will lift her spirits."

They smile at each other, and Sakura thinks she might never tire of looking into those warm sherry-brown eyes. Sharing the flat's small but warm kitchen. Good smells and light notes from the radio, while outside the hectic London world sped on without them. And while it would be even better if Neesan was here too, this is still more than Sakura ever expected.

Everything feels too good to be true, so of course it is. Reality returns in the form of sudden pain. Sharp and bright, it flares up in her left side. It almost sends her reeling to the ground before she manages to catch herself on the table edge.

"Sakura! Sakura, hold on!"

She grits her teeth, distantly registering his arms around her as the hurt crawls through her, along her belly before disappearing into her abdomen. In her mind, she can picture it, white and writhing as it forces its way along inside her. The image remains even after the pain subsides.

"The worms…" Shirou murmurs apologetically. Sorry, as always, that he can't do much to help. That this was something his swords can't cut through.

"It's okay, senpai." The words still comeout a little shaky, but she is starting to feel better. "It gets better the more that we remove. So please don't worry."

"I wish we could go faster."

"I know. But Neesan can only spare so much power at a time." And her body could only stand so much, as they both know but refuse to voice.

"You'll be free soon," he says as he helps her into a chair. "Just a little more, Sakura." He runs a hand comfortingly over her arm. He does it without a twitch of revulsion despite the unspeakable things he'd seen forced out of her, and knows are still buried inside her. She thinks her heart might burst with how much she loves him.

"Yes." She smiles at him. "So don't worry. Here, why don't we clean things up while we're waiting for the trifle to set?"

"Okay, but you let me do that. You need to rest," he says firmly.

She thinks about insisting on helping him, but eventually nods as she gives way to the gentleness in his eyes. Instead she sits at the table and watches him work.

She had never expected to leave the Matou manor, let alone live here in London. But Shirou and Neesan had rescued her during the War, with the help of her senpai's Servant. That had been after Niisan told them about the Matou house. About – she thinks with a hard swallow – about what was being done to her.

Niisan told them, and that was a difficult thing to reconcile with what she thought she knew of her brother. Her skin still bears scars from his more violent tantrums, while her flesh remembers- she shook her head. Still, she is grateful to him.

And grateful to her rescuers, who stole her away from school and spirited her halfway across the world. To London, where Grandfather's influence was much weaker. Not to mention the presence of the Association discouraged more overt attacks, if only for reasons of propriety rather than compassion.

Certainly it didn't solve the problem. Sakura worries about what might be happening back home in Fuyuki. Grandfather does not take well to having his will thwarted, and he has endless patience in enacting his schemes. She worries about what forces he might even now be marshaling, especially with Neesan away from her post as Second Owner. Rin had told her not to worry about it for now. She had made arrangements and pulled in favours to take care of things. She said it with the most sour look on her face, one their classmates would never have imagined the school idol capable of, but she said it just the same. And despite her old instincts screaming at her that it wouldn't work, that no one could save her, Sakura has decided to trust her. Trust _in_ her, and in Shirou.

So here she is, training as her sister's apprentice alongside her senpai. And if her freedom is rather restricted – there was always the risk of magi deciding her Imaginary Numbers made her an ideal specimen – it's still better than what she had experienced over the last decade. Here at least there is sunlight, even if it's filtered through London clouds. Here there is warmth without mockery, touch without pain.

But that's becoming its own form of torture. Constantly being around senpai, knowing he is not repulsed by her despite her taint. Knowing he will always smile at her with genuine warmth. And still not being able to claim him.

Because she has not missed the looks shot between him and her perfect sister.

"Done!"

Shirou's voice is a welcome distraction from her thoughts. She watches as he puts the last plate on the drying rack and hangs up his apron.

He gives a sigh of satisfaction before glancing at the clock. "Nine o' clock. Still a while before Tohsaka gets back." He looks over at Sakura. "Anything you want to do while we wait?"

Yes, plenty. The same things she has so often thought about doing the last few weeks. Neesan has been spending more and more evenings out of the house – busy with research, or social functions, or other engagements. The result is that she has been spending a lot of time alone with senpai lately.

A lot of time for her to reflect on how handsome he is, how kind and gentle. But also about how strong his hands are. How they would feel moving on top of her. Inside her.

Here she is in her sister's home. Benefiting from her sister's work, and her senpai's efforts, on her behalf. And all she can think about is stealing him away to placate her lusts. Disgusting.

"How about a movie?" he asks, oblivious as always to her inner turmoil.

She has many years of practice covering her emotions. So when she smiles and nods at him, he is none the wiser. They settle on the sofa together, and although the urge to grab his hand is almost irresistible, she refrains. But she's not sure how much longer she'll be able to, when she's under constant temptation. And part of her resents that she has to refrain at all. Rin already has so much. Why can't Sakura have this with senpai?

And that isn't even the worst part. If she was just jealous over the boy they both liked, it might not be so bad. They are unworthy thoughts perhaps, but normal thoughts. But Sakura is clearly twisted beyond repair. Truly a disgusting woman. Because she isn't just jealous over Shirou. She's finding herself getting jealous over Rin, too.

Some of it she could excuse as platonic affection for her older sister after a lifetime of estrangement. The fond smile that comes to her as she watches Rin blink, bleary-eyed, over her morning tea. The way her cheeks warm when the raven-haired girl smirks her way, a teasing remark still on her tongue.

But some of it is inexcusable, no matter how she tries to justify it to herself. The twitch in her fingers when she massages Rin's shoulders, forcing her hands on task when she so desperately wants to move them lower and under. The way she lingers in the bathroom as she brushes her teeth, so she can catch a glimpse of enticingly exposed skin when her sister emerges from the shower to preen herself before the mirror. How she trembles at night in their bed, which they share to save space in their small flat but that Sakura finds herself wishing they shared for entirely different reasons.

And sometimes, she finds herself thinking that Rin is not unaffected herself. She's half-convinced that Rin sneaks peeks herself, when she thinks Sakura isn't looking. And that's done nothing to dampen Sakura's desires. On the contrary, it has only fed her hunger.

She truly is a fallen woman.

She is pulled from her thoughts by the sound of a key scraping in their front door's lock. A shuffle ensures, and then Rin stumbles through the small entryway into the living area. Her cheeks are a little flushed, her hair and red evening gown in mild disarray, and she's already kicked off her heels. And still Sakura can't help but find her stunning.

Rin collapses onto the couch beside her. "That stupid drill headed bitch!" she half-growls, half-whines. "Just because I owe her, doesn't mean she can talk to me that way."

There's a particular cloudiness to her normally sharp blue-green eyes. Sakura knows that Shirou sees it too, because he sighs.

"Tohsaka, don't take this the wrong way, but how much have you had to drink?"

"Just a glass… okay, maybe a few glasses. But it was absolutely necessary if I wanted to survive that gulag. Bad enough the harpy was there, but add in Istari and his goons from the Alchemy Department – "

Sakura lets her sister's complaints wash over her with absent-minded hums of encouragement. She's too busy admiring her dress, how it hugs her curves and accentuates her long sculpted legs. She blinks, and the guilt returns tenfold. Not only is she thinking about how much she wants to take Shirou, she's also thinking about her sister in a decidedly inappropriate way. How greedy, all the things she wants from Rin. And a darker part of her isn't the least bit sorry; insists that with all that Rin owes her, she is entitled to this and more.

"- couldn't stand it anymore. It's like there's a conspiracy to strain my last nerve." Sakura tunes back in just in time to see Rin straighten up in her seat.

The magus fixes both Sakura and Shirou with a baleful look. "And you!" she shouts, pointing at the two of them. "Why aren't you fucking like rabbits yet?"

Sakura feels her jaw drop open in astonishment at her sister's words, even as the guilt surges through her. Because she's certainly thought about it tonight. A lot. And judging from the deep blush that has joined the shock on Shirou's face, maybe her senpai isn't quite as oblivious as she'd assumed. How terrible she is, that she can feel pride and joy in knowing he shares her fantasies, even in a situation like this.

Shirou clears his throat. "Tohsaka," he manages, "We're not doing anything like that."

"And that's the problem!" snorts Rin. "No matter how many chances I give the two of you, you just won't go for it. What kind of man are you, anyway?" She leans back against the cushions, and she must have had quite a bit to drink, because otherwise she would never allow the pinpricks of tears forming in her eyes. "How much more are you going to make me do here? This isn't much fun for me, you know."

Sakura looks at her sister in surprise. "Wait, Neesan. You… you wanted us to? Is that why you've been spending so much time outside the flat? To give us opportunities?"

Rin sighs heavily. "Sakura, look. I know this place is kind of a prison for you. You barely know anyone here. You can't go back to visit in Fuyuki, because we can't risk the old bastard getting a chance at you. You constantly have to watch your step at the Clocktower – hell, in London as a whole. You need something to look forward to everyway." She waves a hand, with rather less than her usual grace. "And, well, you're never been shy about your feelings for the idiot."

Shirou 's brain finally seems to spring back into action at this last bit. "Wait, Sakura? You really feel that way?" He scratches awkwardly at the back of his neck. "I thought it was just me reading too much into thi-"

"Oh my god!" explodes Rin. "How are you this impossible? Why do you think I went so far to save you, when you got your idiot self killed by Lancer?" She points in Sakura's direction. "For her sake!"

And yours too, thinks Sakura to herself. Rin is a selfish person, despite what she thinks she's trying to do here.

Rin turns back to Sakura. "Anyway, I wanted you to have something good. To make up for being trapped here. I was hoping to be a bit more subtle about it, but argh." She closes her eyes and massages her temples.

"Neesan…" Sakura tries to sort through her conflicting emotions. She is deeply touched on the one hand. Rin loves Shirou, for all her aloof demeanour, and it means a lot that she would give him up for Sakura's sake. But it is that same fact that also deeply annoys her. Because in her stubborn conviction that she knows what's best for everyone, Rin is setting them all up for unhappiness.

Not to mention that Rin has no ground to call senpai impossible. Not when it's been months, and she's still in the dark about Sakura's feelings.

She opens her mouth to scold her sister, when Shirou abruptly rises from his seat. He moves so that he is standing directly in front of the seated Rin, who can only watch him warily.

"Tohsaka," he says, then snaps his finger back to flick her forehead.

"Ouch! What was that for?"

"Don't just make these decisions by yourself," he says reproachfully. "Don't I get a say in who I date?"

The word _love_ hangs in the air. But where it might once have made Sakura's heart clench painfully, now it fills her with hope. Because if it's there, and she's not wrong about the other things she's seen, then maybe, just maybe –

It's a risk, a definite risk. She cannot expect her feelings to be met with anything but shock, horror and disgust. But if she wants this, she has to strike now, while the concept still hangs there. Before Neesan retreats into her pride, and Shirou into his embarrassment.

So she clears her throat and takes the plunge. "Senpai is right," she says, and she can feel their surprise at the boldness in her voice. "I appreciate the sentiment, but you've missed some important things."

Because I love senpai, and so do you. And he loves both of us. And even if the world will never approve, even if it will make things endlessly difficult for all of us, I love… I love… Sakura comes to a decision, in that moment. The first she's been able to freely make for herself in a long time.

"You can't tell me you don't like him," says Rin, "Not with the way you look at him, and everything you've done for him." And it must have been good wine, because she leans forward and says, "And you can't tell me you haven't thought about all the filthy things you want to do with him."

"Tohsaka -!" Shirou squawks.

Sakura beams at both of them, even as her heart hammers in her chest. "Oh no. I'm proud to say that I love senpai. And I would _very_ much like to do all those things with him."

"Sakura…" murmurs Shirou, even as he goes bright red.

"But there's someone else too. I watched her for years from a distance, after we were separated. She was the shining star I always coveted. When I was living in the Matous, and I was unhappy –" they both flinch, but still she continues, "I was so jealous of that star that I hated it. Why did she get to shine so brightly, while I suffered in the dark?"

Rin looks down and opens her mouth to say something, when Sakura gently presses a finger against her lips. Forces her head back up to look at her. "But that star finally came for me, to help me. Along with my hero," and she looks tenderly at Shirou, who stares back at her helplessly. "How could I not want them both?"

There is a long moment of silence, then Rin swallows heavily. "I love you too, Sakura."

Sakura feels elation run through her, like liquid light in her veins.

The Rin continues, and her words are an iron weight dragging her back down to earth. "You're my sister, and I'll always be here to support you –"

"Not just like that!" says Sakura. "I love you. The other way too, I mean." She thinks her blush might rival the rising sun's, but she forces herself to look into her sister's startled eyes. After a lifetime of hiding in the shadows, she wants all her feelings laid out in the light.

There is utter silence from the other two as she looks anxiously between them. If Shirou were any redder, he would be on fire. Rin is not much better, wide-eyed and skin flushed. They both look so cute, Sakura thinks, and she wants to commit this image to memory. Because this is likely the last time she will see it, seeing as now they must reject her, now that they know what kind of girl she is. And yet as heart-wrenching as it will be, she still cannot find it within herself to regret.

"No, nope. Nuh-uh," says Rin suddenly, in a low voice, as if she is talking to herself more than Sakura. "You're my little sister. I can't do that to you. Even if you do have the nicest pair of… ugh, I am way too drunk for this."

Sakura blinks, then smirks – an expression she never dared indulge in before, but one she has readily picked up here in London. "You like my breasts?" She leans forward, pushing her best assets forward for better inspection. "Do you want to touch them?"

The way that Rin can't tear her eyes off her chest says it all. "Sakura," she whines. "If you aren't serious, please stop. I don't think – I can't –" And isn't that a sight, her razor-tongued sister floundering in search of words.

But maybe words aren't what is needed to prove sincerity right now. Sakura's never been that good with them, anyway. So instead she leans forward and kisses Rin.

Her heart jumps when after some hesitation, the other girl responds. Their mouths move together in a dance that starts off tender before picking up heat. It lasts a while before they both pull back for air.

"This has got to be a dream," says Shirou weakly, "The cream must have gone bad, and now I'm seeing things."

"Is it a good dream?" she asks as she turns to him, grinning.

"Yeah, of course, but –"

He shuts up when Sakura presses her lips against his in turn. After a moment, he throws away his doubt and kisses her back. It is a rougher kiss than the one she shared with her sister, but just as pleasant. And when Sakura glances to the side, she sees hunger, not jealousy, in Rin's eyes as she watches them.

She is positively beatific when their lips inevitably separate again.

Shirou bites his lip, his intention to chase written all over his face, when he suddenly looks at Rin and winces. But she only looks away with a small huff which does nothing to hide the blush on her cheeks.

Most of all, they both look lost, and Sakura realizes she will need to be the one to lead this. She has never really lead anything before. Her role in the Matou household firmly pushed her into the role of follower, if not passive object. But she finds that this time, she is happy to lead. She has a destination in mind, after all.

"It's getting late," she says gently. "Why don't we all go to bed? We can talk about it in the morning."

Shirou shakes his head in wonder. Rin looks like she wants to argue, like it's unbelievable to leave something so life-shattering to the morning, but she doesn't know where to even start the deeper discussion that must follow. So neither of them resists when Sakura tugs them both by the wrists towards their bed. Hers, and Neesan's, and Shirou's now too, if she has anything to say about it.

Somehow clothes are removed and bodies shuffled into bed, with less fuss than anyone expected. Perhaps they are all too physically exhausted and emotionally unbalanced to make it as awkward as it probably should be. And while the bed is a tight fit – especially with the way Rin holds herself stiffly off to one side – Sakura is content. She is warm and safe, surrounded by the two people she loves. The only two people she can imagine allowing into her heart.

There will be lots of confused feelings to work out and negotiations to be done tomorrow, but Sakura is sure she can win them over. She is pretty sure that Shirou is already most of the way there, from the way he looks at the both of them, and because he wants everyone to be happy. Neesan (no, Rin, she must call her by name now since she wants a bond beyond sisters) will be a tougher nut to crack. Especially once she's sober. But Sakura is sure she'll give in. Because Sakura can see it in her eyes, now that she's allowing herself to see it – the longing for Sakura's touch.

She doesn't care what the world will say. The world already declared that they weren't sisters, the day it allowed Sakura to be taken to the Matou. And even if the world has changed its mind, she will not change hers. Because she will not let the rules of a world that abandoned her tear away her newfound happiness. Now that she has been freed from her shackles, she is not going to waste any time hesitating.

She rolls over onto her side, pushing up against Rin's back. At the same time, she reaches for Shirou's hand. He follows her guiding touch, goes further to wrap his arms around her.

For the first time in more than a decade, Sakura does not fear the night.

* * *

**Bonus scene**

Sakura hums as she washes the dishes from the day's lunch. Several weeks on, and things have settled down quite nicely.

There are still some… quirks in their relationship. Shirou keeps blinking at his two partners, as if he can't quite believe he's allowed to be this happy. Rin is constantly muttering about how she's never going to hear the end of it when their current arrangement leaks out, especially from the blonde devil. There are some things that are highly unorthodox even by the flexible morality of magus society, after all. And Sakura would be lying if she said she didn't have harbor some doubts herself.

But the doubts are slowly fading, as they all slowly grow more comfortable with each other. Even if the perfect relationship can never be grasped, it will be alright so long as they keep reaching for it together.

"I'm home," calls Rin from the doorway as she comes in. "There's a package for you, Sakura."

Sakura rinses her hands as she looks over her shoulder and sees the plain brown box tucked under her sister's arm. "Oh good. I've been looking forward to this."

Rin, always curious to a fault, is looking over the package's label. "Huh, just a line for the return address. And it says these are… pot holders?" She crinkles her nose in confusion. "Do we need pot holders?"

"Why don't we open it together, Rin?" It still feels odd not to call her Neesan or Tohsaka-senpai, but that's the kind of thing that will come in time.

She sets the box on the dining room table. Rin eagerly tears in, without as much as a by-your-leave. After a moment, she takes out an array of joined straps of black cloth and dangles it in front of her for inspection.

"Huh, is this some kind of harness?" Then she looks down at the piece of moulded red silicone tucked in the box beneath it. A very definite shade of pink rises in her cheeks. "Sakura, what is this?"

Sakura gives her a bright smile, with perhaps just an edge of slyness. "Well, the harness goes over your hips to – "

"I know what a strap-on is!" interrupts Rin, as her blush deepens. "I mean, why is it here?"

"I want to try something new. I'm always on the receiving end, so I want to try switching things up a bit."

Rin raises her eyebrow. "You want to peg Shirou?"

"Definitely, if senpai is up for it," says Sakura sweetly. "But before that, I want to try it on you. That's why I ordered it in your favourite color."

Rin's mouth snaps shut, her face as red as the toy. She works her mouth open and closed several times, until she finally manages," A- as if I'd ever try something so embarrassing." She drops the harness back into the box and walks off, rather stiffly.

Sakura giggles to herself. It seems like another round of negotiations will be in order. Although, judging from Rin's reaction, she thinks she can expect another crushing victory.


End file.
